Electron tube mount



Jan. 12, 1960 A. w. BLOOM ET AL 2,921,209

ELECTRON TUBE MOUNT Filed Jan. 4, 1956 2 Sheets-Sheet 1 1 mam 7m; flrzzolaliifillzkzmfilaom AUZyff 175% X M E a Y Jan. 12, 1960 A. w. BLOOM ET AL 2,921,209

ELECTRON TUBE MOUNT Filed Jan. 4, 1956 2 SheetsSheet 2 I T l' 8L0 1 llllullll W T r\\\\ ,fn

l8 1- ,2.2 20 1a A, l irzzah lg United States Patent 7 2,921,209 ELECTRON TUBEMOUNT Arnold W. Bloom and Roy K. Wolke, Maplewood, N.J., assignorsto Radio Corporation of America, a corporation of Delaware Application January 4, 1956, Serial No. 557,336

' The present invention is concerned with the art of electron tube mounts, and relates in particular to improvements in electrode cages for such mounts. Electrode cages of electron tubes commonly include electrodes that comprise at least a cathode and an anode, and a pair of insulating spacer plates sandwiching these electrodes between them for positioning the electrodes in a desired relation with respect to each other.

I Previous plural cage-electron tubes have usually had all of the components thereof assembled into a single, plural cage structure in a manner wherein a defective or missing component in any one of the cages resulted in a.

scrapping of the entire structure. Typically, such prior structures have had all of the electrodes of the separate cages mounted between a single pair of spacer plates. 'The practice of mounting the electrodes of all of the cages between a single pair'of spacer plates has required the use of relatively complicated and costly machinery in 'multi-cage structure by available assembling techniques.

It is thereforean object of the invention to provide an improved plural cage structure for an electron tube and which lends itself to relatively low cost assembling techniques.

- It is another object of the invention to provide in an electron tube an improved plural cage structure that is comprised of relatively simple, self-supporting sub-assembly structures.

The foregoing and related objects are accomplished in .an electron tubestructure including two elongated, sideby-side electrode cages each having two spacer plates. Both of the plates of each cage have a portion extending from a side thereof and overlapping a portion of a plate of theother cage, and with the overlapping portions fixed to each other.

:In making such a plural cage structure the two cages are separately assembled into two self-supporting units, and then the units are positioned in side-by-side relation so thatjadjacent spacer platesof each cage are in contact. The adjacent spacerplates are then fixed together to form a composite, self-supporting structure. The technique of first separately assembling the separate'cages of the plural cage structure and then integrating the sub-assemblies thus formed into a complete plural cage structure is of particular advantage. This advantage resides in the fact that presently available machines, which are used for making v the fact that each individual cage of a multiple cage 2,921,209 Patented Jan. 12, 1960 ice structure according to the invention is a self-supporting structure.

The invention is described in greater detail in the drawing where like numerals refer to like parts, and wherein:

Fig.1 is a partially cut-away side elevational View of an electron tube mount incorporating the invention;

Fig. 2 is a sectional view taken through line 22 of Fig. 1;

Figs. 3 and 4 are views illustrating, respectively, two successive steps in the manufacture of the tube shown in Figs. 1 and 2;

Fig. 5 is a top plan view of a plural cage structure em bodying another aspect of the invention; and

Figs. 6 and 7 are top plan and side elevational views, respectively, of a plural cage structure embodying yet another form of the invention.

Fig. 1 illustrates an electron tube having electrode access terminals or prongs 4 at one end thereof and an envelope 6 containing a plural cage mount 10 comprised of two elongated, side-by-side cages, for example a triode and a tetrode cage, 12 and 14, respectively. Each of the cages 12 and 14 includes a pair of relatively flat spacer plates 16, 18, and 20, 22, respectively.' Each of the spacer plates of one pair 16 and 18 are positioned in contact with and fixed to a spacer plate of the other pair 20 and 22.

The triode cage 12 has, mounted between its two spacer plates 16 and 18, a cathode 24 surrounded by a wound grid 26, the grid 26 being made up of a pair of side rods 28 having a lateral grid wiring 30. The grid 26, in turn, is surrounded by a sheet metal anode 32. The tetrode cage 14 has, mounted between its two spacer plates 20 and 22, a cathode 34 surrounded by a pair of concentric wound grids 36 and 38 each having a pair of side rods, 40 and 42, respectively, and a lateral grid winding, 44, and 46, respectively. The grids 36 and 38, in turn, are surrounded by a sheet metal anode 48. Each of the electrodes referred to has a portion at each of its opposite ends, 24', 26, 34, 36', 38', and 48, respectively, extending through the spacer plates of its cage. The electrodes are maintained in position within the tube 2 by means of the plates 16, 18, 20, and 22. i

The two spacer plates of each cage are spaced the same distance apart as the spacer plates of the other cage, and each plate has a transverse extent spanning the electrodes of its own cage and overlapping an adjacent spacer plate of the other cage. .Thus, as shown in Fig. 1, adjacent plates 16 and 20. and adjacent plates 18 and 22 are shown overlapped. The overlapping portions of the spacer plates 16, 18, 20, and 22 each have, respectively, an aperture 50, 52, 54, and S6. The apertures are in axial registry with each other. A pin 58 extends through the apertures for locking adjacent spacer plates to each other. The pin 58 has a head 60 at one end thereof and a bentover portion 62 at the other end for securing the pin to the plates in a rivet-like bond. The pin has an embossment 64 adjacent to its bent-over portion 62 for securing between the embossment and the bent-over portion two of the adjacent spacer plates to effect a more secure union of the two cages 12 and 14.

As shown in Fig. 2, spacer plates 16 and 20 have slits 66 extending radially from the apertures therein. These slits 66 enable the spacer plates to flex in a direction radially away from the apertures therein to enable the embossment 64 (Fig. 1) to slip through the apertures during the assembly of the two cages into a plural cage mount. It will be noted in Figs. 1 and 2 that the inwardly facing edges 18a and 20a of the innermost spacer plates 18 and 20 terminate each in contact with an adjacent edge of the anode 48 and 32, respectively, of the other cage. Furthermore, the contacting edges of thespacer plate and the anode have complementary registry with each other.

axial registry with each other.

contours to provide a relatively large area surface of contact between them. This contact secures the two cages 12 and 14 from rotation about the pin 58. Thus a relatively secure self-supportingjplural-cage,mount is provided which is made up of two cages fixed-together by a single pin, and which is relatively rugged by virtue Of the contact adjacency between-a spacerplate'of each While the-spacer cage with the anode of the other cage. plates 18 and in the tube of Figs. 1 and 2 are shown having edges 18a and 20a which are relatively straight, and each edge in contact with the side of an anode32 and 48 having flat sides, it will-be appreciated that the anode sides and their contacting spacerrplate'edges may have contours different from that shownin Fig. 2- as long -as the portions in contact are complementary toeach other, that is, are suitably shaped so that adjacent :portions have relative large area contacts. Thus, for example, the anodes of the two cages may instead each have a circular transverse extent and the spacer plate edges, of the other cage in contact with the anode of the first cage, have a concave contour embracing the anode.

Referring now to Figs. 3 and 4 there is illustrated the method by which the plural cage mo'unt of the invention is assembled. As shown in Fig. 3, the 'two separate, self-supporting cages 12 and 14, after being separately assembled, are each placed on a difierent half, 70 and 72, respectively, of an assembly jig. The upper surfaces of the two halves 70 and 72 of the assembly jig are so oriented that, when the cages 12 and 14 are each supported by the jig, the upper surfaces 74 and76'of the two spacer plates 20 and 22 of one cage 14 are'at-the same vertical height as the lower surfaces 78 and 80 a each other, in direction A, until, as shown in Fig. 4,

the apertures 50 to 56 of the spacer plates are inaxial The pin 58 is then inserted into the apertures aforementioned from a positionabove the apertures. The pin 58 has a tapered lower end 82 and one of the jig halves 72 has a recess 84 forming'an anvil shaped to bend the pin end'82 in a horizontal direction in a manner similar to the bending of a free end of a wire staple in a stapling machine. The pin end 82 is tapered so as to allow it to bend without bending the body of the pin 58. The bending of the'pin end 82 secures the pin to the plates thus integrating the two cages 12 and 14 into a unitary structure.

The method described may be varied in order to insure against the chance of the edges of adjacent spacer .plates meeting in abutting relation (in which case the plates might be broken). of the higher jig half (numbered 70 in Fig. 3) may be The cage supporting surface maintained at a sufficient distance above that of the ward each other (as explained with reference to Fig. 3) until the apertures 50 to 56 of the spacer plates are in Then the cages are moved axially toward each other into the position shown in Fig. 4, and the pin 58 is inserted into the-apertures and lo'cked to the plates.

Fig. 5 illustrates another aspect of the invention. The plural cage mount 90 has two pins 92 and 94 for integrating the two self-supporting cages 96 and 98 into a single mount. Each of the pins 92 and 94 are inserted into the spacer plates (of which only the upper two 100 and 102are illustrated) by a method-similar to that-shown in Figs. 3 and-4. Hofwever, sin'ce two pins -92"and'94 are used in the mount 90 of Fig. 5, each of =the an0des 104 and 106 of the plural cage-mount 90 '-may have :a contour different from that-of the adj acent said cages,

edge of a spacer plate of the adjacent cage. Thus, for example, each of the anodes 104 and 106 may have a circular cross section while the adjacent spacer plates of the other cage have straight edges.

Figs. 6 and 7 illustrate a plural cage mount 110 embodying another form of the invention. In the form illustrated in these figuresthe'adjacent edges of each of the two spacer plates '112,'1-14,'and 116,118 of, respectively, cages and 122, are digitate. As shown in Fig. 6, spacer plate-112 has three digits "124, '126;and128, and spacer plate 116 has two "digits 'and21'32. "The digits of these two spacer plates 112 and'116 are interdigitated with each other for locking theaplatesatoveachpother. Similarly, the other .adjacent spacer plates 114 and 118 (Fig. 7) are digitate an'd'avith the digits of each plate interdigitated with the digits of the other plate.

The digitate, plural cage structure 110 not only provides a relatively securelocking of ,the two 'cagesj120 and 122=to each other, but aalso allows the structure to conform to envelope irregularities. The structure conforms to envelope irregularities since the digitate arrangement permits of asmall-angular-adjustment of the cages with each other. Thisangular adjustment letsall of the edges of the spacer plates -at portions remote from the digits contact the envelope wall.

'In fixing adjacent spacerplates 112and 116, aud 114 and 118 together,alternate-digits of each plateare-fiexed in opposite directions (as shown in Fig. 7) and'then adjacent plates are moved toward each other until the digits are interdigitated with each other. The friction between engaging digits locks the-adjacent plates together.

While the digits are preferably :tapered-as shown in the drawing, it'will be appreciated-that the digits may have other contours. For example. thetdigits'may each have a substantially rectangular contour.

From the foregoing it is seen thatthe invention provides an improved plural cage electron tubesstructure which lends itself to relatively lowqcosbassembling. techniques by being madesupuofrelatively simple, SGIfrSUP- porting sub-assemblies.

wfixing said cages into a unitary'structure.

2. An electron tube mount comprising two elongated, self-supporting electrode cages each .havinga pair of spaced-apart spacer plates, each of the-spacerplates of one pair having a portion lapped-overxa; portion of a spacer plate of the other pair, each'of-the' lapped portions of adjacent spacer plates'having edges defining apertures in axial registry, and .a pin extending through said apertures of said adjacent plates'for fixing said cages into a unitary structure.

3. An electron tube mount comprising two elongated electrode cages each having-a pair'of spaced-apart spacer plates, each of the spacer plates of one pair having a portion lapped over a portion of a spacerplate-of the other pair, each of the lapped portions of adjacent spacer plates havingedges 'definingapertures inaxial registry, and means extending'through said-apertures of said adjacent plates for fixing said cages intoaunitary structure,'each of the spacer plates of oneof said-cages abutting-a portion -of the other-of said cages between the plates of said last named cage,-"-the-abutting portions of the spacer plate of-" s'a'id one bf said cages -and the cage portion of said other of *saidcages' haVing complementary contours for contributing to the fiXed-en'gagement-of 4. An electron tube mount comprising two elongated electrode cages each having a pair of spaced-apart spacer plates, each of the spacer plates of one pair having a portion lapped over a portion of a spacer plate of the other pair, each of the lapped portions of adjacent spacer plates having edges defining apertures in axial registry, and a pin extending through said apertures of said adjacent plates for fixing said cages into a unitary struc ture, each of the spacer plates of one of said cages abutting a portion of the other of said cages between the plates of said last named cage, the abutting portions of the spacer plate of said one of said cages and the cage portion of said other of said cages having complementary contours for contributing to the fixed engagement of said cages.

5. An electron tube mount comprising two equally elongated, self-supporting electrode cages each having a pair of spaced-apart spacer plates, each of the spacer plates of one pair having a portion lapped over a portion of a spacer plate of the other pair, each of the lapped portions of adjacent spacer plates having edges defining apertures in axial registry, and means extending through said apertures of at least two of said adjacent plates for fixing said cages into a unitary structure.

References Cited in the file of this patent UNITED STATES PATENTS 2,034,365 Wise Mar. 17, 1936 2,048,023 Parker July 21, 1936 2,253,208 Miller Aug. 19, 1941 2,340,670 Lehman Feb. 1, 1944 2,355,717 Eitel et al Aug. 15, 1944 2,518,308 Gronros et a1. Aug. 8, 1950 2,644,998 Klinker et a1. July 14, 1953 2,836,746 Wolke et a1. May 27, 1958 2,840,735 Ruzinsky June 24, 1958 

